Engine starter



July 13, 1937. E. 1.. WALKER ET AL ENGINE STARTER Filed Sept. 4, 1934 2 Sheets-Sheet 1 m E M K T Mm w WD LM T s w E H w m H July 13, 1937. E. 1.. WALKER ET AL 2,087,009

ENGINE STARTER Filed Sept. 4, 1954 2 Sheets-Sheet 2 ERNEST L. WALKEA l5 A. l HND EQIIMHMIQ! QRTHUIZT Pwmm Patented July 13, 1937 i'i' E STA'ES 2,8'Ltt ENGINE STARTER Application September 4, 1934, Serial No. 742,613

Claims.

This invention relates toa starting mechanism for internal combustion engines and having means whereby a kick back of the engine will not damage the parts of the starter.

Heretofore, difiiculty has been experienced in starters wherein the engine has been driven by a torsion spring, which tends to become broken upon a kick back of the engine when attempts are made to start the same. Other devices have been devised with a view to eliminate this torsion spring driver, but certain defects have prevented their smooth operation to displace the torsion spring type.

It is an object of this invention to provide a starter for internal combustion engines in which a part-ialrotation of the starter shaft will cause engagement of the driving pinion of the starter with the fly Wheel of the engine, and a further partial rotation of the starter shaft will cause complete engagement between the pinion and the fly wheel and in case of kick back of the engine, the pinion will automatically become disengaged from the engine and the parts will assume their normal position without damage to the parts of the starter.

It is a. further object of this invention to provide a starter for internal combustion engines in which a cam surface will move the driving pinion into partial engagement with the fly wheel of the engine and whereby another cam surface will cause complete engagement between the pinion and the engine, with a third cam surface for allowing the parts to assume normal position in case of kick back of the engine during the starting thereof.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawings, in which:--

Figure 1 is an elevation of my invention showing the parts in an inoperative position;

Figure 2 is a longitudinal sectional View taken along the line 2-2 in Figure 1;

Figure 3 is a view similar to Figure l but showing the parts in a slightly different position immediately after the shaft of the motor has rotated a few degrees;

Figure 4 is another view similar to Figure 3 but showing the position of the parts after the motor shaft has advanced a few more degrees to cause the gears to be in operative position, with the point of View following the rotation of the shaft;

Figure 5 is a view similar to Figure 4 but sho-W ing the position of the parts when a kick back occurs in the engine, the point of view following the rotation of the shaft;

Figure 6 is a detail View of the sleeve adapted to operate on the main shaft of the electric motor;

Figure"? is a cross-sectional View taken along line 1-1 in Figure 4.

Referring more specifically to: the drawings, the numeral ll] denotes an electric motor having a shaft H rotatably mounted therein, the other end of said shaft being journaled in housing l2. A sleeve I3 is loosely mounted on shaft l l and is confined thereon. by any suitable means such as shoulder bolts M and l 5 which penetrate the L-shaped slots It and ll respectively, in the enlarged portion of the sleeve it. It is seen that this sleeve has a limited rot'ative movement on shaft ll since the pins it and i5 are mounted in the slots 66 and ill. (Fig. 7). It isfurther seen that slots l6 and I l have adjoining slots 18 and i9 respectively, (Fig. 6), which extend approximately at right angles. from the slots; l6 and I! and which are adapted to receive the pins M and I5 when a kick back in the engine occurs. This feature is shown in Figure 5 and will be described presently.

A compression spring 20 is confined around the shaft II and normally has one end resting against the end of motor l0 and the other end against the end of sleeve l3. By providing aspring of this type the sleeve i3-is normally pressed to the right at all times against the pins 14 and it. The sleeve It has a restricted portion 2| and also a pair of spirale'd prongs 22 and 23 which are raised above the restricted portion 2|. This forms slots 24 and 25 into which prongs; 2t and 27 are adapted to-slide, prongs 2t and H being integral with one end of a sleeve 28 which has cut therein a gear'29. GearZQ is adapted to mesh with a similar gear 30 which is mounted on the fly wheel ofthe engine.

Confined on portionZl of sleeve I3 is a sec ond coil-spring?! by'm'eans of s1eeve' 28 and a collar 32, said collar 32 being secured onshaft it by any suitable means such as pin 33. It should be noted that spring 3| is relatively weak with respect to the other springs and only tends to hold the pinion 29 out of engagement with the gear 30 when the automobile is going down an incline.

By referring to Figures land 2 it is seen that a flanged collar til normally encircles and is secured to the left-hand portion of collar 28. This collar reinforces the prongs Z6 and 21 and causes them to be held firmly in position when they engage the prongs 22 and 23 of sleeve I3. A spring 4| is secured, by any suitable means such as welding, to the left-hand portion of collar 4%] and to the right-hand portion of collar 43, said collar 43 having notches or indentations M and 45 in the side thereof for the reception of heads of pins I4 and I5. The spring 4i resiliently forces the pinion 29 into engagement with gear 39 when the shaft II is first rotated. Spring l-I, even though made of the same gauge material, being of greater circumference is much weaker than spring 20 and therefore is compressed before spring 20.

When the current is supplied to the motor I0 and the shaft II begins to rotate the parts first assume the position as shown in Figure 3, that is, pin I4 engages the upper portion of the slot I6 and pin I5 occupies a corresponding position in slot IT. This movement causes pins I4 and I5 to ride out of indentations M and 45 to force member 43 slightly to the right.

Since the collar 40 has been omitted from the sleeve 28 in Figure 3, it is seen that the prongs 26 and 21 of sleeve 28 have been forced partially out of slots 24 and 25 in the member I3. It is further noted that pinion 29 has slightly engaged the teeth in the pinion 35. This movement to the right of collar 28 is produced by the first partial rotation of shaft II.

If for any reason the gears 29 and 30 should not be in the exact position to mesh, the member 43 would move to the right and gear 29 would not engage the teeth in pinion 39 until shaft It had rotated sufficiently to cause them to engage. The spring 4! would be compressed until the gears rotated to a proper position to mesh.

Since prongs 26 and 21 frictionally engage the slots 24- andv 25 in member I3, upon further rotation of shaft I I, from the position shown in Figure 3, the prongs 26 and 21 will continue to slide out of slots 24 and. 25 to cause pinion 29 to fully engage the pinion 32. (See Fig. 4.) In this position the gears are in operative position and spring 3I has been compressed the maximum amount. The fricti n of prongs 22 and 23 against prongs 26 and 21 together with the friction of bolts I4 and I5 in their respective slots, is sufficient to turn the motor of an automobile. If for any reason an excessive load is suddenly applied to pinion 29, such as a kick back of the automobile engine, the parts will assume the position as shown in Figure 5. In this figure the bolts I4 and I5 have engaged. the slots l8 and I9 and member I3 has moved to the left to compress spring 20. Prongs 22 and 23 have also moved practically out of engagement with prongs 26 and 21. Upon a slight further movement or back lash of the motor, the parts 22 and 23 as shown in Figure 5, will ratchet over members 26 and 21 to cause prong 26 to engage slot 25 and the prong 27 to engage slot 24. The parts in Figure 5 are shown in a position immediately before this ratcheting effect takes place. It is thus seen that I have provided a friction drive which will allow a back lash in a motor to occur with out endangering or breaking the parts in the starter. When a direct drive is used such as a torsion spring, a kick back of the engine frequently breaks a spring and damages other parts of the starter.

In the drawings and specification there has been set forth a preferred embodiment of the invention and although specific terms are employed, they are used in a generic and descriptive sense only, and not for purposes of limitation, the

scope of the invention being set forth in the appended claims.

We claim:

1. A starter for internal combustion engines provided with a fly wheel gear, comprising a driven shaft, a sleeve slidably mounted on said shaft, an approximately L-shaped slot in said sleeve, a pin secured in said shaft and slidably penetrating said slot, a torsion spring surrounding said shaft and normally forcing said pin into the shorter leg of said L-shaped slot, a spiral groove in said sleeve, a second sleeve slidably mounted on the first sleeve and having a pro jection slidably fitting into said spiral groove, a pinion on the second sleeve for engaging said gear wheel.

2. In a starter for an internal combustion engine having a fly wheel gear, a driven shaft, a sleeve slidably mounted on the shaft, a second sleeve slidably mounted on the first sleeve and having a pinion thereon for engaging the fiy wheel gear, a pin projecting from. said driven shaft, a cam surface on the second sleeve engageable by said pin to move the pinion into engagement with the fly wheel gear, a second cam surface on the first sleeve engageable by the second sleeve for moving the pinion into further engagement with the fly wheel gear, and a third cam surface on the first sleeve engageable by the pin for driving the two sleeves, a torsion. spring normally forcing the first sleeve towards the fly wheel gear but allowing the first sleeve to move with relation to the pin when the resistance of the engine exceeds a predetermined force.

3. A starter for an engine having a flywheel gear comprising a driven shaft, 2. pair of sleeves slidably mounted on said shaft, a pinion fixed on one sleeve, cooperating cam means between the sleeves, other cam means between the shaft and the other sleeve for advancing the pinion into engagement with the engine upon rotation of the shaft for a portion of one revolution, the other cam means between the sleeves. serving to further advance the pinion into further engagement with the engine upon further rotation of the shaft, and a lost motion driving connection between the shaft and said other sleeve whereby two sleeves are moved longitudinally of the shaft by said other cam means before rotation is imparted by the shaft to the two sleeves.

4. An engine starter comprising a driven shaft, a pair of sleeves slidably surrounding the shaft, a pinion fixed on one sleeve, cam means between the pinion sleeve and the other sleeve, other cam r means between the shaft and the sleeve having the pinion thereon whereby a slight turning of the shaft will move the pinion into engagement with the engine before rotation is imparted to the sleeve, a lost motion connection between the shaft and the other sleeve whereby further turning of the shaft will move the other sleeve which in turn will move the pinion fartherinto engagement with the engine.

5. An engine starter comprising a driven shaft, a pair of sleeves slidably surrounding the shaft, a pinion fixed on one sleeve, earn means between the pinion sleeve and the other sleeve, other cam means between the shaft and the pinion sleeve thereon whereby a slight turning of the shaft will move the pinion into engagement with the engine, a lost motion connection between the shaft and the other sleeve whereby the pinion is moved into engagement with the engine before rotation is imparted thereto and whereby further turning of the shaft will move the, other sleeve which in turn will move the pinion farther into engagement with the engine, and resilient means carried by the sleeve having the pinion thereon for resiliently forcing the pinion into engagement with the engine.

6. An engine starter comprising a driven shaft, a sleeve slidably surrounding said shaft, a lost motion connection between the shaft and sleeve, a second sleeve slidably mounted on the first sleeve and having a pinion thereon for engaging the engine, a cam connection between the shaft and the second sleeve, a spiral cam connection between the sleeves, slight rotation of the shaft serving to move the second sleeve longitudinally of the shaft while the first sleeve is unaffected due to the lost motion connection with the shaft, and further rotation of the shaft serving to turn the first sleeve and advance the second sleeve and its pinion farther into engagement with the engine.

7. An engine starter comprising a driven shaft, a sleeve slidably surrounding said shaft, a lost motion connection between the shaft and sleeve, a second sleeve slidably mounted on the first sleeve and having a pinion thereon for engaging the engine, a cam connection between the shaft and the second sleeve, a spiral cam connection between the sleeves, slight rotation of the shaft serving to move the second sleeve longitudinally of the shaft while the first sleeve is unafiected due to the lost motion connection with the shaft, a further rotation of the shaft serving to turn the first sleeve and advance the; second sleeve and its pinion farther into engagement with the engine, a longitudinally and spirally extending cam connection between the shaft and the first sleeve whereby the second sleeve may move the first sleeve longitudinally of the shaft when the second sleeve is subjected to undue strain, and spring means resisting such longitudinal movement of the first sleeve.

8. An engine starter comprising a driven shaft, a sleeve slidably mounted on the shaft, a second sleeve slidably mounted on the first sleeve and having a pinion thereon for engaging the engine, spiral cam connections between the sleeves whereby turning of the first sleeve will advance the second sleeve, a lost motion driving connection between the shaft and the first sleeve, cam. means between the shaft and the second sleeve operable upon initial turning movement of the shaft to move the second sleeve longitudinally of the first sleeve to cause the pinion on the second sleeve to engage the engine.

9. An engine starter comprising a driven shaft, a sleeve slidably mounted on the shaft, a second sleeve slidably mounted on the first sleeve and having a pinion thereon for engaging the engine, spiral cam connections between the sleeves whereby turning of the first sleeve will advance the second sleeve, a lost motion driving connection between the shaft and the first sleeve, cam means between the shaft and the second sleeve operable upon initial turning movement of the shaft to move the second sleeve longitudinally of the first sleeve to cause the pinion on the second sleeve to engage the engine, cam means between the first sleeve and the shaft whereby the first sleeve may move longitudinally of the shaft when the resistance of the engine places undue strain on the second sleeve and spring means resisting such longitudinal movement.

10. An engine starter comprising a driven shaft, inner and outer sleeves slidably mounted with relation to each other and to said shaft, a pinion fixed on the outer sleeve for engaging the engine, spiral cam means between the sleeves, a lost-motion cam driving connection between the shaft and the inner sleeve, a cam connection between the shaft and the outer sleeve whereby initial turning of the shaft will move the pinion on the outer sleeve into engagement with the engine before the lost motion cam driving connection becomes effective to move the pfnion farther into engagement with the engine.

11. An engine starter comprising a driven shaft, a sleeve slidably mounted on the shaft, said sleeve having a circumferential slot and a longitudinally and spirally extending slot communicating with each other, a pin in the shaft and extending normally through said circumferential slot, a compression spring normally holding said pin in said circumferential slot, said sleeve having a spirally disposed groove therein, a second sleeve surrounding the first sleeve and having a pinion for engaging and driving the engine, said second sleeve also having a projection extending into said spiral groove, said first sleeve also having a cam engageable by said pin while traveling in the circumferential slot to move the pinion into engagement with the engine before the pin reaches the point of junction of the two grooves to move the first sleeve to in turn advance the pinion on the second sleeve farther into engagement with the engine.

12. An engine starter comprising a starter shaft, a pin extending from the shaft, a sleeve slidably mounted on the shaft and having a cam slot therein penetrated by said pin, spirally dis- ,posed prongs projecting from one end of said sleeve, a second sleeve slidably mounted on the shaft and having spirally disposed prongs projecting from one end thereof and inter-engaging the prongs on the first sleeve, a pinion on the second sleeve, a third sleeve mounted for sliding movement on the first sleeve and having a resilient connection with the second sleeve, a cam portion on the third sleeve engageable with said pin upon slight rotation of the shaft to move the second sleeve and its pinion with relation to the first sleeve and to cause the pinion to engage the engine, the shaft upon further turning movement carrying with it the first sleeve to thereby advance the second sleeve and its pinion into complete engagement with the engine.

13. A starter for an engine having a fly wheel gear comprising a driven shaft, a pair of sleeves slidably mounted on said shaft, a pinion fixed on one sleeve, cooperating cam means between the sleeves, other cam means between the shaft and the other sleeve for advancing th pinion into engagement with the engine upon rotation of the shaft for a portion of one revolution, the other cam means between the sleeves serving to further advance the pinion into further engagement with the engine upon further rotation of the shaft, a torsion spring normally forcing said other sleeve towards the fiy Wheel gear but allowing said other sleeve to move away from the pinion when the resistance offered by the engine exceeds a predetermined force.

14. A starter for an engine equipped with a toothed fly wheel comprising a driven starter shaft, first and second overlapping sleeves on said shaft and being slidably mounted with relation to each other and to said shaft, the sleeves having adjoining cam surfaces, a pinion fixed on the first sleeve for engaging the fly Wheel,

resilient means normally forcing the sleeves toward but not in contact with the fly wheel, a cam driving connection between the shaft and said second sleeve, a cam driving connection between the shaft and the first sleeve whereby a partial revolution of the shaft will move the pinion into engagement with the fly Wheel, and

the first sleeve for engaging the fly wheel, resilient means normally forcing the sleeves toward but not in contact with the fly wheel, a cam driving connection between the shaft and said second sleeve, a cam driving connection between the shaft and the first sleeve whereby a partial revolution of the shaft will move the pinion into engagement with the fly wheel, and further movement of the shaft will cause the cam driving connection between the shaft and the second sleeve to move the pinion further into engagement with the fly wheel, the resilient means allowing movement of the second sleeve away from the first sleeve when the resistance offered by the engine is above a predetermined force.

ERNEST L. WALKER. ARTHUR T. PITTMAN. 

